Produção de mudas cítricas interenxertadas em sistema hidropônico

Abstract

In the search for new technologies aimed at circumventing the incompatibility of 'Pear' orange on 'Flying Dragon' and Citrumelo 'Swingle' rootstocks, the use of inter-grafting may be a viable solution. However, in the conventional system of propagation of citrus seedlings, even with the use of such a technique, a longer time for formation is required, besides the high percentages of seedlings discard. Hydroponics can be a viable alternative technique, as it has been outstanding for providing quality seedlings in a shorter time. Thus, the present paper aims at evaluating the grafting methods envisioning the production of orange seedlings on the 'Flying Dragon' and the Citrumelo 'Swingle' rootstocks, using the 'Cravo' lemon tree as a graft in the hydroponics system. To make this research feasible, two steps were necessary and, in the first one, we employed two grafting methods (sub grafting and forging) in two rootstocks. The design used in the first experiment was completely randomized (CRD), consisting of four treatments, ten replications and five plants per plot, totaling 200 seedlings. In the second experiment, seedlings from the best treatments (foraging) of the first stage were used. These seedlings were grafted by foraging and bubbling. We also used the design in CRD, with six treatments (3 rootstocks and two grafting methods), five replications and five plants per plot, totaling 150 seedlings. Both stages were carried out in a hydroponic system, located on the roof of the Botanical Garden of the Department of Agriculture of the Federal University of Lavras (UFLA). We concluded that in the first experiment the seedlings obtained by the roasting method with the 'Flying Dragon' rootstock resulted in higher viability and development rates. Whilst in the second experiment the treatments with the grafted tree orange 'Pêra' seedlings presented results of setting, the average height of the seedlings and the average diameter of the main stem very similar to those obtained without the use of the graft. Therefore, the hydroponic system is a viable alternative for the production of interplanted citrus seedlings.